Coal-washing apparatus.



E. P. DANDRIDGE & J. B. CESSNA.

GOAL WASHING APPARATUS. APPLIOATIOH nLnn JAN. 18, 1910.

Patented May 31,1910.

JVENTOR WITNESSES UNITED STATES PATEN QFFIGE.

EDMUND 1. DANDBID G-E AND JOHN B. CES$1 A, OF PITTSBURG, PENNSYLVANIA.

COAL-WASHING- APPARATUS.

Specification of Letters Patent.

Patented May 31, 1910.

Application filed January 18, 1910. Serial No. 538,768.v

To all whom it may concern:

Be it known that we, EDMUND P. DAN- DRIDGE and JOHN B. CESSNA, citizens of the United States, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invente certain new and useful Improvements in Coal-Washing Apparatus, of which the following is a specification, reference being had therein to the accompanying, drawing.

Our invention refers to improvements in washing apparatus for coal or other minerals and for the separation of impurities therefrom by gravity and the buoyant effect of water.

The invention relates particularly to an improved construction of overflow conduit for the refuse or waste material, nounted upon the supporting screen adapted to discharge the slate etc., to the cavity below the screen, as it accumulates thereon. In connection with the said overflow conduit we utilize an upwardly extending shell adapted to separatethe main portion of the .accumulated impurities from the upper end of the outlet: conduit, which is preferably provided with an adjustable terminal, the outer shell also constituting an air chamber, constructed and adapted to operate in the manner more fully hereinafter set forth.

In the drawings: Figure 1 is a longitudinal vertical sectional view through a washing apparatus provided with our improvement. Fig. 2 is a plan view of Fig. 1. Fig. 3 is an enlarged sectional detail view of the refuse overflow controlling device.

The washing apparatus shown in the drawings is one of well known construction and comprises a jig tank 2, preferably rectangular in form, having inwardly and downwardly sloping ends 3, 3, a transverse partition 4: separating the washing chamber 5 from the usual plunger or pulsationproducing compartment 6. The upper portion of the washing. chamberor compartment 5 is separated from the lower or impurity collecting slate bin portion 7 by a transversely arranged screen 8 of perforated material, wire netting, or other suitable construction to separate the mineral to be washed and to provide free upward travel of the water.

9 is a slate gate of any suitable form controlling the outlet for the impurities at the bottom of the tank.

10 is a supply chute from a bln, etc., by

which the raw coal is discharged upon the screen 8, and 11 is the overflow chute for the washed coal and water.

Water is supplied to the pulsation compartment 6 at the other end of the tank by a suitable supply pipe 12, and for the purpose of producing pulsation of the water to cause intermittent travel thereof through the screen 8, any suitable means may be utilized.

In the drawings we have shown means for providing intermittent pneumatic pressure consisting of a valve 13 mounted within a suitable casing 14 and arranged to be intermittently shifted to one side or the other by pressure of air within the storage tank 15, connected to the casing by suitably arranged connections 16 registering with supply ports, which ports in turn register with corresponding parts in valve 13 at the limits of its movement in each direction, causing it to shift back and forth to intermittently bring a central port 17 of the valve into register with the middle connection 16 to supply an intermittent air pressure to produce the de sired pulsations.

The present invention does not particularly relate to the valve or air supply mechanism, and we have only shown and described the same generally, it being understood that valve 13 is shifted, either by the air pressure of any desired degree or by mechanical means to initiate and cut off the air supply, according to the work to be done. 4 In the separation of the impurities from the coal, the intermittent pulsation of the water up through the perforated screen 8 operates in the usual manner, the lmpurities settling at the bottom and forming a bed 18 which it is desired to maintain at or about a certain predetermined thickness. It is also desirable to carry off the accumulated materials as they are precipitated in addition to the amount required to form the bed, for which purpose we; provide the outlet pipe 19 extending upwardly through screen 8 at any suitable point, as the middle thereof, which pipe is preferably provided with -an adjustable terminal 20 screwed into pipe 19, or otherwise arranged. The purposeof terminal 20 to vary the inlet terminal point of pipe 19, to regulate the flow of the impurities within the controlling conditions or in roportion to the rate accumulated, etc.

urrounding the upper portion of outlet 19 and its terminal 20, with an annular space 21, and spaced above the screen 8 by supporting legs 22, is a surrounding shell 23. Said shell is closed at its upper portion by a head 24 preferably having a controlling valve 25 to release the air from the interior through port 26 or to maintain said port closed. When maintained closed and'water is supplied to the tank to the normal working level, it will rise within the shell 23 against a confined air cushion at the upper portion thereof, which air cushionwill, to an extent, absorb the vibration of the water within the shell and assist in the undisturbed circulation of the impurities thereinto from the exterior and upwardly toward the inlet terminal of pipe 19.

The operation will be readily understood from the foregoing description. Coal being discharged on the screen 8 and pulsation being imparted to the water within the tank, separation of the heavier impurities is accomplished and they will accumulate to the desired level and escape underneath to the interior of shell 23 and thence downwardly through pipe 19 to the slate bin, from which they are removed from time to time.- The adjustment of the terminal member 20 provides for varying the operation as to capacity, quality, etc, while the mechanism is comparatively simple and cheap and will continue to operate without getting out of order.

The invention obviates the necessity of the usual slate gates for drawing oif the accumulated refuse from time to time and renders the operation of the jig automatic.

It will be understood that one or more of the outlet controlling devices for the impurities may be utilized according to the size or other characteristics of the apparatus, and that it may be otherwise changed or varied by the skilled mechanic, but all such changes are to be considered as within the scope of the following claims:

What we claim is,

1. In a washing apparatus of the class described, the combination with the tank and its perforated screen, and means for imparting pulsations to the water in the tank, of a conduit pipe extendin through the screen to the interior cavity ol t its open lower end within the tank, an inlet pipe having a freely open upper inlet end adj ustably mounted in the upper end of said pipe, and a surroundin shell concentrically spaced away from said conduit and above the screen providing a circulation space for impurities and having a closing head and a valve controlled air port, substantially as set forth.

2. In a washing apparatus, the combination of a main tank having a dividing partition providing a washing compartment at one side and a pulsation compartment at the other side thereof, means for supplying water to the pulsation compartment and for producing pulsations therein, a discharge gate for impurities at the base of the tank, a screen arranged across the washing compartment provided with a vertically disposed conduit pipe leading to the interior lower portion of the tank and having adjustably secured in its upper end a terminal inlet pipe, a surrounding shell spaced above the screen and concentrically around the pipe and providing an air chamber, and means for supplying raw material to the screen and for leading off the washed mineral, substantially as set forth.

In testimony whereof we aflix our signatures in presence of two witnesses.

EDMUND P. DANDRIDGE. JOHN B. CESSNA.

\Vitnesses:

O. M. CLARKE, CHAS. S. LEPLEY.

he tank and having 

